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Not What You Meant?  There are 37 definitions for FS.  Also try: C1 or SSA or Pad or RS.

C0 and C1 control codes

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The C0 and C1 control code sets define control codes for use in text. C0, originally defined in ISO 646, defines codes in the range 00HEX–1FHEX. C1, originally defined in ISO 6429, defines codes in the range 80HEX–9FHEX. The C0 codes are contained in ASCII and most encodings based on it. The C1 codes were included in the ISO-8859-n series of encodings and Unicode but are rarely used directly, except on specific platforms such as OpenVMS. When they turn up in documents, Web pages, e-mail messages, etc., which are ostensibly in an ISO-8859-n encoding, their code positions generally actually refer to the characters at that position in a proprietary, system-specific encoding such as Windows-1252 or the Apple Macintosh ("MacRoman") character set, though this is technically invalid under the ISO encodings. Such characters are more commonly accessed using the equivalent two octet escape sequence. Most applications only interpret the C0 control codes for LF, CR, and HT. A few applications also interpret C0 codes VT and FF, and the C1 code NEL. Very few applications interpret the other C0 and C1 control codes.

Contents

C0 (ASCII and derivatives)

Seq Dec Hex Abbr Character name Description/notes
^@ 00 0x00 NUL Null Originally used to allow gaps to be left on paper tape for edits. Later used for padding after a code that might take a terminal some time to process (e.g. a carriage return or line feed on a printing terminal). Now often used as a string terminator, especially in the C programming language.
^A 01 0x01 SOH Start of Heading First character of a message heading. In some computer terminals, moves cursor to the first column.
^B 02 0x02 STX Start of Text First character of message text, and may be used to terminate the message heading.
^C 03 0x03 ETX End of Text Often used as a "break" character (Ctrl-C) to interrupt or terminate a program or process. In TOPS-20, it was used to gain the system's attention before logging in.
^D 04 0x04 EOT End of Transmission Used on Unix to signal end-of-file condition on, or to logout from, a terminal. On Apple II systems, it signaled that a DOS command followed.
^E 05 0x05 ENQ Enquiry Signal intended to trigger a response at the receiving end, to see if it is still present. In some computer terminal and EMACS , moves the cursor to the end of current line.
^F 06 0x06 ACK Acknowledge response to an ENQ, or an indication of successful receipt of a message.
^G 07 0x07 BEL Bell Originally used to sound a bell on the terminal. Later used for a beep on systems that didn't have a physical bell. May also quickly turn on and off inverse video (a visual bell).
^H 08 0x08 BS Backspace Move the cursor one position leftwards. On input, this may delete the character to the left of the cursor.
^I 09 0x09 HT Horizontal Tab Position to the next horizontal tab stop.
^J 10 0x0A LF Line Feed On typewriters, printers, and some terminal emulators, moves the cursor down one row without affecting its column position. On Unix, used to mark end-of-line. In MS-DOS, Windows, and various network standards, used following CR as part of the end-of-line mark.
^K 11 0x0B VT Vertical Tab Position the form at the next vertical tab stop.
^L 12 0x0C FF Form Feed On printers, load the next page. Treated as whitespace in many programming languages, and may be used to separate logical divisions in code. In some terminal emulators, it clears the screen.
^M 13 0x0D CR Carriage Return Originally used to move the cursor to column zero while staying on the same line. On Mac OS (pre-Mac OS X), as well as in earlier systems such as the Apple II and Commodore 64, used to mark end-of-line. In MS-DOS, Windows, and various network standards, it is used preceding LF as part of the end-of-line mark. The Enter or Return key on a keyboard will send this character, but it may be converted to a different end-of-line sequence by a terminal program.
^N 14 0x0E SO Shift Out Switch to an alternate character set.
^O 15 0x0F SI Shift In Return to regular character set after Shift Out. In TOPS-20, it signalled that further output should be discarded; the program would continue to run but not display or print anything until ^O is typed again.
^P 16 0x10 DLE Data Link Escape Cause the following data to be interpreted as raw data, not control codes.
^Q 17 0x11 DC1 Device Control 1/XON Resume transmission. Used for software flow control. In some terminal programs, ends pause started with Ctrl-S.
^R 18 0x12 DC2 Device Control 2 In TOPS-20, reprinted the current line, tidying up any character deletions.
^S 19 0x13 DC3 Device Control 3/XOFF Suspend transmission. Used for software flow control. In some terminal programs, pauses display of text.
^T 20 0x14 DC4 Device Control 4 In TOPS-20, it caused a brief system-status line to be displayed.
^U 21 0x15 NAK Negative Acknowledge Sent by a station as a negative response to the station with which the connection has been set up. In binary synchronous communication protocol, the NAK is used to indicate that an error was detected in the previously received block and that the receiver is ready to accept retransmission of that block. In multipoint systems, the NAK is used as the not-ready reply to a poll. In some text editors, it was used as a "Delete Line" character.
^V 22 0x16 SYN Synchronous Idle Used in synchronous transmission systems to provide a signal from which synchronous correction may be achieved between data terminal equipment, particularly when no other character is being transmitted. In some terminal programs, allows literal entry of control codes without them being interpreted.
^W 23 0x17 ETB End of Transmission Block Indicates the end of a transmission block of data when data are divided into such blocks for transmission purposes. In some text editors, it is used as a "Delete Word" character which rubs out the previous text entry back to the preceding space.
^X 24 0x18 CAN Cancel Indicates that the data with which it is associated are in error or are to be disregarded, or cannot be represented on a particular device.
^Y 25 0x19 EM End of Medium In many programs, a keyboard input of Ctrl-Y is a "redo" command to undo the last Ctrl-Z undo command.
^Z 26 0x1A SUB Substitute On MS-DOS systems with files opened in text mode, "end of text" or "end of file" is marked by the Ctrl-Z character (code 26, "Substitute"), instead of ^C or ^D common on other operating systems. In many programs, a keyboard input of Ctrl-Z is an "undo" command to reverse the most recent input or action. In many terminal programs, this will suspend the active process and return control to the shell.
^[ 27 0x1B ESC Escape The ESC key on the keyboard will cause this character to be sent on most systems. It can be used in software user interfaces to exit from a screen, menu, or mode, or in device-control protocols (e.g., printers and terminals) to signal that what follows is a special command sequence rather than normal text.
^\ 28 0x1C FS File Separator Can be used as delimiters to mark fields of data structures. If used for hierarchical levels, US is the lowest level (dividing plain-text data items), while RS, GS, and FS are of increasing level to divide groups made up of items of the level beneath it. These can usually be generated by holding down Ctrl and the backslash, right square bracket, caret, and underscore keys respectively.
^] 29 0x1D GS Group Separator
^^ 30 0x1E RS Record Separator
^_ 31 0x1F US Unit Separator
^? 127 0x7F DEL Rubout/Delete Originally used to mark deleted characters on paper tape, since any character could be changed to all ones by punching holes everywhere. On VT100 compatible terminals, this is the character generated by the key labelled ⌫, usually called backspace on modern machines, and does not correspond to the PC delete key.

C1 (ISO 8859 and Unicode)

Dec Hex Esc Seq Short Abbr
(RFC 1345)
Full Abbr Character name Description/notes
128 0x80 0x1B 0x40 PA PAD Padding Character listed as XXX in unicode
129 0x81 0x1B 0x41 HO HOP High Octet Preset
130 0x82 0x1B 0x42 BH BPH Break Permitted Here
131 0x83 0x1B 0x43 NH NBH No Break Here
132 0x84 0x1B 0x44 IN IND Index Deprecated in 1986 and withdrawn in 1991 from ISO/IEC 6429 (ECMA-48)
133 0x85 0x1B 0x45 NL NEL Next Line Used to mark end-of-line on some IBM mainframes.
134 0x86 0x1B 0x46 SA SSA Start of Selected Area
135 0x87 0x1B 0x47 ES ESA End of Selected Area
136 0x88 0x1B 0x48 HS HTS Horizontal Tab Set
137 0x89 0x1B 0x49 HJ HTJ Horizontal Tab Justified
138 0x8A 0x1B 0x4A VS VTS Vertical Tab Set
139 0x8B 0x1B 0x4B PD PLD Partial Line Forward Used to produce subscripts and superscripts in ISO/IEC 6429, e.g., in a printer.
Subscripts use PLD text PLU while superscripts use PLU text PLD..
140 0x8C 0x1B 0x4C PU PLU Partial Line Backward
141 0x8D 0x1B 0x4D RI RI Reverse Line Feed
142 0x8E 0x1B 0x4E S2 SS2 Single-Shift 2
143 0x8F 0x1B 0x4F S3 SS3 Single-Shift 3
144 0x90 0x1B 0x50 DC DCS Device Control String
145 0x91 0x1B 0x51 P1 PU1 Private Use 1
146 0x92 0x1B 0x52 P2 PU2 Private Use 2
147 0x93 0x1B 0x53 TS STS Set Transmit State
148 0x94 0x1B 0x54 CC CCH Cancel character
149 0x95 0x1B 0x55 MW MW Message Waiting
150 0x96 0x1B 0x56 SG SPA Start of Protected Area
151 0x97 0x1B 0x57 EG EPA End of Protected Area
152 0x98 0x1B 0x58 SS SOS Start of String
153 0x99 0x1B 0x59 GC SGCI Single Graphic Char Intro listed as XXX in unicode
154 0x9A 0x1B 0x5A SC SCI Single Char Intro
155 0x9B 0x1B 0x5B CI CSI Control Sequence Introducer
156 0x9C 0x1B 0x5C SI ST String Terminator
157 0x9D 0x1B 0x5D OC OSC OS Command
158 0x9E 0x1B 0x5E PM PM Private Message
159 0x9F 0x1B 0x5F AC APC App Program Command

References

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C0 and C1 control codes from Wíkipedia. ©2006 by Wíkipedia. Licensed under the GNU Free Documentation License. View a list of authors or edit this article.

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